US Patent 7536103 Reconfigurable optical switching system

The switching system comprises a routing device having selection modules each having one input and a plurality of outputs adapted to switch spectral channels received selectively to respective outputs as a function of a command. The routing device comprises a first stage comprising a plurality of modules whose inputs constitute the input ports of the device, a second stage comprising at least one first selection module whose outputs constitute the output ports of the device, and an intermediate stage for coupling the input of the first selection module of the second stage both to a first output of a first selection module of the first stage and to a first output of a second selection module of the first stage. The switching system applies to interconnection panels in switching nodes for optical networks.